Enter The World of Machined Springs...

International Space Station spring

The spring

for the 21st century

Here's why:

Advanced machined spring technology

Finite element stress analysis (FEA) with Ansys

Modal analysis

Accommodates a wide variety of integrated attachments

Includes pure spring reactions for torsional applications

Incorporates multiple start configurations to eliminate extraneous reaction forces and moments, (buckling)

Provides unlimited variations

Offers multi-functionality expertise

The HELI-CAL® Flexure

The HELI-CAL Flexure is a flexible helix (curved beam) machined into a unique configuration that incorporates special design requirements, performance features and/or characteristics. The material used is basically unlimited.
When used as a spring, the multifunctional flexure provides desired and predictable elastic performance in compression, extension, torsion, lateral bending and lateral translation modes.

One huge advantage of this technology—it enables customer specified end-attachments, such as tangs, clamps, flanges or threaded ends, to be integrated into a single multi-functional component.

Materials:

High strength corrosion resistant materials such as stainless steel

High strength aluminum

High strength titanium

All machinable alloys

Machinable plastics

Materials most used: Stainless steel 17-4PH, 15-5PH, 303, 316, 416, 18-8, Custom 455 maraging,C300 and C250, 718, 4340, H-11, Beta C Titanium, Delrin 150, Aluminum 7075-T6.

Capabilities/Services

Over 40 years of manufacturing and engineering excellence

Complete in-house engineering design and manufacturing

Quality assurance

Precise spring rates

Prototypes and short runs to high volume production quantities

Fast turn around and delivery

Unmatched dedication to quality and customer satisfaction

“Multi-start” flexure construction (more than one spring coil set) provides a broad range of spring rates and
functionality within a given envelope. Provides a redundant coil to resolve lateral forces.

Precision machining of complex, multi-featured configurations

Wire-wound vs HELI-CAL machined springs

Differences in coil geometry enable machined springs to provide more precise performance, features and functions than can other, more traditional types of springs. There are big differences in performance, reliability, versatility, integrity, and cost effectiveness. See example below.

Before
Wire-wound spring.
Three pieces

After
Helical machined spring. Single piece.
Integrated parts-functions.

The bottom line —machined springs:

Offer more functions in a single spring than other more traditional springs, such as wire-wound.
Add value, in terms of multipart integration, time saved in handling, reliability, rates being linear, and dimensions being very precise.
Reduce and/or control costs.
Raise overall productivity, i.e., add more, do more, save more dollars.

Comparison Data — are machined springs right for your application?

Consideration Wire-wound
springs Machined
springs Comments

Perform basic elastic modes Yes Yes Machined springs have distinct multi-functional advantages.

Relatively inexpensive Can be Depends Both types can be expensive or inexpensive.

Available in different materials Limited Yes Machined springs can be produced from any
machinable material.

Multi-function - feature capability Limited Yes Machined springs can contain many dimensional features.

No stress to overcome before deflection Some Yes Machined springs have a more precise force deflection relation.

Can reduce assembly costs Doubtful Yes Incorporating multiple features into a single part
design makes assembly easier & cost effective.

Can contain redundant elastic elements (multiple starts) No Yes Machined spring rates are linear.

Quality - reliability Depends on manufacturer Yes Dimensional variances are typically smaller in
machined springs.

Precision elasticity Difficult Yes Variation rates in machined springs are typically
low.

Integration with other products Difficult Yes Design it into your system, not around it.

Reduction of system complexity Difficult Yes Simplify your system by incorporating multiple
capabilities into a single part.

Custom-end configurations added to spring With difficulty Yes One of the major advantages of machined springs.

Longevity achievable? Yes Yes Machined spring’s long life can benefit from multi-start configurations (double and triple starts).

Can be configured as:
Machining lends itself to custom end attachments. With machined springs, all coils deflect under load.

Extension spring

Yes

Yes

Compression spring Yes Yes

Torsion spring Yes Yes

Lateral bending spring ? Yes

Lateral translation spring ? Yes

Applications utilizing the HELI-CAL® Flexure range from missiles to medical apparatus to oil wells

Integrated attachment examples of Helical machined spring

Threaded ID and OD Integrated flange Double start flexure Heat dissipating spring

Hubble telescope
Aerospace application Cryogenic cooler application Used with lasers

Material: Beta C Titanium Right and left handed flexure Threaded ends Capacitor terminal

240° torsional spring Triple start, torsional spring Mars Rover Aircraft electronics

Formerly four pieces Tapered flange Beefed up radius on tangs Four elastic rates incorporated

Now one piece with Helical wrap spring clutch Single start,
compression spring One piece, wrap spring clutch Medical application
Five start spring

Constant pivot and rotary Material: 17-4PH Integrated end attachments .125” Flexure OD

Medical application
Torsion spring Industrial knife application Machine tool application Commercial lateral spring